Quantum Computation

This CCIS 2733 project constitutes the refereed post-conference proceedings of the 4th CCF Quantum Computation Conference, CQCC 2025, Chengdu, China, during July 21–23, 2025.The 11 revised full papers presented in these proceedings were carefully reviewed and selected from 50 submissions. The papers are organized in the following topical sections:Quantum Computing, Quantum Machine Learning, Quantum Simulation, Quantum Walks, Variational Quantum Algorithms, Quantum Circuit Optimization, Quantum Security, Quantum Cryptanalysis, Quantum Metrology, Hybrid Quantum-Classical Systems